#Write a function that takes two parameters.
#Both of them are non-empty array of integers.

#Find the pair of numbers whose absolute difference is closest to zero.

#arrayOne = [-1, 5, 10, 20, 28, 3]
#arrayTwo = [26, 134, 135, 15,  17]

#Find the pair of numbers whose absolute difference is closest to zero.
def smallest_difference(arrayOne, arrayTwo):
    arrayOne.sort()
    arrayTwo.sort()

    numbers = []
    numbers_sum = []

    for i in range(len(arrayOne)):
        for j in range(len(arrayTwo)):

            one = arrayOne[i]
            two = arrayTwo[j]

            if one > two:
                numbers.append(one - two)               
            elif two > one:
                numbers.append(two - one)

    numbers.sort()

    for k in range(len(arrayOne)):
        for l in range(len(arrayTwo)):

            one_sum = arrayOne[k]
            two_sum = arrayTwo[l]

            if one_sum - two_sum == numbers[0] or two_sum - one_sum == numbers[0]:

                numbers_sum.append(one_sum)
                numbers_sum.append(two_sum)

    return numbers_sum

print(smallest_difference([-1, 5, 10, 20, 28, 3],[26, 134, 135, 15, 17]))